Alan,
Sure, if the law is in place, you should take advantage of it. I don't disagree with you there for sure.
I just think that it's a silly way to decide who pays taxes. Any other business with equipment and land that produces income has to pay full property tax on it. But again, that's just my opinion. Seems like it would be better to tax you on what you make off of your equipment/land. In your case, you'd likely pay very little in tax or not bother to farm at all. That makes sense, since you can't possibly make any money anyway.
I am also looking on this from a land stewardship perspective. If everyone who had ten to 50 acres managed it with the best interests of the environment as their main concern, we wouldn't have a lot of the problems now present.
And yes, I do believe that farmers can manage their business with the environment as a factor. In fact, farmers are a vital part of almost any wildlife/watershed management approach. However, it's a lot easier to consider the environment and make necessary changes to your operation if you have a few hundred or thousand acres.